1. Field of the Invention
The present invention relates generally to programmable integrated circuits (ICs), and more particularly to signal processing in field programmable gate arrays (FPGAs).
2. Description of Related Art
Field programmable gate arrays are often selected by design engineers to provide a flexible approach in programming and re-programming integrated circuits in order to accommodate a system specification, correct errors in the system, or make improvements to the system by reprogramming the FPGA. One conventional field programmable gate array architecture is implemented using groups of look-up tables and programmable interconnect circuits. While the look-up tables and sequential elements are connected to each other, the connections to the groups of look-up tables typically originate from a switchbox located in each group of the look-up table. A hierarchical interconnect structure connects to elements in a look-up table through a switchbox, thereby serving as the primary source of connecting look-up tables from one logic block to another logic block. The inputs to the look-up tables are therefore generated primarily from the switchbox. The look-up table outputs are directly fed to other look-up tables as well as the elements within the look-up tables, but the connections to other look-up tables' inputs are made through the switchbox.
In another conventional structure, a majority of the inputs required for performing all functionality of configurable logic blocks are typically restricted to inputs associated with a particular configurable logic block, other than through the use of the switch box. The same is true for outputs of a particular configurable logic block which are restricted to within the configurable logic block other than through the use of the switch box.
Efforts have been mounted to improve the overall performance of field programmable gate arrays. It is desirable to have a method that improves the performance of programmable integrated circuits for use with innovative hardware solutions.